硬质合金表面构筑类金刚石碳膜及其水环境摩擦学性能

发布时间：2018-04-30 22:14

本文选题：磁控溅射 + 硬质合金　；参考：《江西理工大学》2017年硕士论文

【摘要】：硬质合金作为“工业的牙齿”在水环境下有着重要的应用,然而水环境下复杂工况会导致硬质合金发生严重的磨损,这使得开发高性能的减摩耐磨薄膜材料来防护硬质合金零部件以降低其磨损破坏显得十分重要。因此,本文采用磁控溅射系统在硬质合金表面制备了含氢a-C:H薄膜、典型金属元素掺杂的Me/a-C:H薄膜以及稀土元素Ce协同典型金属复合掺杂的(Me,Ce)/a-C:H薄膜,并系统地考察了所制备的碳基薄膜的微结构和力学性能,并考察了其在大气环境和去离子水环境下的摩擦磨损行为。主要研究结果如下:1.在硬质合金表面构筑了纯的a-C:H薄膜材料,其微结构呈现出典型的非晶特征,且薄膜表面光滑,力学性能较好;虽然纯的a-C:H薄膜在大气环境下能获得较好的摩擦学性能,但由于水环境下其对水分子敏感,薄膜容易出现失效现象。2.采用典型金属Ti、Cr元素掺杂来改善纯的a-C:H薄膜,从而在硬质合金表面分别构筑了Ti/a-C:H和Cr/a-C:H碳基薄膜;结构表征显示两种碳基薄膜均表现出典型的非晶/纳米晶结构特征,Ti元素以TiC的纳米晶分布在Ti/a-C:H薄膜中,而Cr元素以Cr的纳米晶分布在Cr/a-C:H薄膜中;金属元素掺杂薄膜的力学性能得到一定程度的改善,两种薄膜的硬度与弹性模量以及结合强度出现上升,且内应力降低;并且,硬质合金表面构筑的Ti/a-C:H和Cr/a-C:H碳基薄膜体系在大气环境下和去离子水环境下均能表现出较好的摩擦学性能。3.稀土元素作为材料有效的改性剂,采用稀土Ce元素协同典型金属元素Ti、Cr掺杂,以进一步提升碳基薄膜的性能,从而在硬质合金表面分别构筑了稀土增强的(Ti,Ce)/a-C:H和(Cr,Ce)/a-C:H碳基复合薄膜体系;结构表征显示两种稀土增强的碳基复合薄膜均为非晶结构,Ti元素以TiC的纳米晶分布在(Ti,Ce)/a-C:H薄膜中,Cr元素以Cr的纳米晶分布在(Cr,Ce)/a-C:H薄膜中,然而Ce元素以非晶态的CeO2分布在两种薄膜中;引入稀土元素Ce有效的促进了碳基薄膜的硬度与弹性模量以及结合强度进一步提升,且有效的释放了内应力;尤其是在大气环境下与去离子水环境下,硬质合金表面所构筑了稀土增强的(Ti,Ce)/a-C:H和rCr,Ce)/a-C:H薄膜体系能够表现出更加优异的的低摩擦和高耐磨特性。
[Abstract]:As "industrial teeth", cemented carbide has an important application in water environment. However, complex working conditions in water environment can lead to serious wear and tear of cemented carbide. This makes it important to develop high performance antifriction and wear resistant film materials to protect cemented carbide parts from wear damage. Therefore, a-C:H thin films containing hydrogen, Me/a-C:H films doped with typical metal elements and rare earth elements ce / a-C: h films were prepared on cemented carbides by magnetron sputtering system. The microstructure and mechanical properties of the carbon based films were systematically investigated, and the friction and wear behaviors of the films in atmosphere and deionized water were also investigated. The main results are as follows: 1. Pure a-C:H thin films were fabricated on the surface of cemented carbides with typical amorphous microstructure, smooth surface and good mechanical properties, although the pure a-C:H thin films can obtain better tribological properties in atmospheric environment. However, due to its sensitivity to water molecules in water environment, the film is prone to failure. 2. 2. Ti/a-C:H and Cr/a-C:H carbon based films were fabricated on cemented carbides by doping the typical metal Ti-Cr to improve the pure a-C:H films. The structural characterization of the two carbon-based films shows that the typical amorphous / nanocrystalline structure of Ti is distributed in the Ti/a-C:H films as the nanocrystalline of TiC, while Cr is distributed in the Cr/a-C:H films as the nanocrystalline of Cr. The mechanical properties of metal-doped films were improved to some extent. The hardness, elastic modulus and bonding strength of the two films increased, and the internal stress decreased. The Ti/a-C:H and Cr/a-C:H carbon-based film systems constructed on the surface of cemented carbide have good tribological properties in atmosphere and in deionized water. Rare earth elements are used as effective modifiers to improve the properties of carbon based films. Thus, the rare earth reinforced TiCe / a-C: h and CrCX / a-C: h composite films were constructed on the surface of cemented carbides, respectively. The results of structural characterization show that the two rare earth reinforced carbon based composite films are amorphous Ti elements, which are distributed in TiC nanocrystalline in TiCe / a-C: h thin films as Cr nanocrystalline in CrCX / a-C: h thin films. However, ce is distributed in two kinds of thin films as amorphous CeO2. The introduction of rare earth ce can effectively improve the hardness, elastic modulus and bonding strength of carbon based films, and release the internal stress effectively. Especially in the atmosphere and deionized water environment, the rare earth reinforced TiCU / a-C: h and rCrCrCna-C / H thin film systems can exhibit better low friction and high wear resistance on the cemented carbide surface.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG174.4;TG135.5

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